A computationally efficacious free-energy functional for studies of inhomogeneous liquid water

TL;DR

This paper introduces a simple, computationally efficient free-energy functional for inhomogeneous water that accurately captures key physical properties, making it useful for mesoscale and ab initio solvation studies.

Contribution

The authors develop a new free-energy functional for water based on a minimal microscopic Hamiltonian with four parameters, enhanced with a range parameter for improved accuracy.

Findings

Accurate equation of state for water with minimal parameters.

Captures short-range correlations and cavitation energies.

Suitable for mesoscale water and ab initio solvation applications.

Abstract

We present an accurate equation of state for water based on a simple microscopic Hamiltonian, with only four parameters that are well-constrained by bulk experimental data. With one additional parameter for the range of interaction, this model yields a computationally efficient free-energy functional for inhomogeneous water which captures short-ranged correlations, cavitation energies and, with suitable long-range corrections, the non-linear dielectric response of water, making it an excellent candidate for studies of mesoscale water and for use in ab initio solvation methods.